Data is physically stored at physical storage locations within physical storage media. Examples of the physical storage media include magnetic disks, optical disks, magneto-optical disks, solid state drives, etc. Physical storage media may also include hybrids which are combinations of two or more different types of physical storage media. For example, physical storage media may be implemented as a combination of a solid state drive and a rotating platter drive.
Data physically stored in physical storage media is organized in a disk file maintained by an operating system. A disk file is partitioned into multiple logical blocks, where each logical block is mapped or assigned to physical storage locations within the physical storage media. Data organized within a particular logical block may be accessed by reading or writing to physical storage locations that are assigned to the particular logical block. Data organized within a particular logical block, may be referred to herein, as data logically stored on the particular logical block.
The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section.